Retrievable vented packer for oil wells



3 Sheets-Sheet 1 Nov. 18, 1969 Filed July 7, 1967 F/G. 1'. f

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Nov. 18, 1969 w. w. HlcKl-:Y 3,479,064

RETRIEVABLE VENTED PACKER FOR OIL WELLS Filed July 7. 1967 3Sheets-Sheet 2 arroz/Veys.

United States Patent O 3,479,064 RETRIEVABLE VENTED PACKER FOR OIL WELLSWeldon W. Hickey, 401 W. Fowler, Medicine Lodge, Kans. 67104 Filed July7, 1967, Ser. No. 651,727 Int. Cl. F161 17/ 00, 33/16, 47/00 U.S. Cl.285-111 5 Claims ABSTRACT OF THE DISCLOSURE This invention relates to adevice which may be used to isolate any desired section of theproduction casing in a well when the particular section has been piercedby either natural or artificial means.

It is a particular object of this invention to provide a device asaforesaid which not only will seal off a desired section of casing,thereby sealing off the break or puncture which appears within thatsection of the casing, but will permit pressure of oil and/or gas in thecasing below the device to be vented while the device is in use.

It is a further object of this invention to provide a device asaforesaid which, while sealing off perfectly a predetermined section ofcasing which has been broken or pierced, is itself retrievable and doesnot interfere with retrievability of the casing itself.

It is a further object of this invention to provide a device asaforesaid which may be handled by standard tube handling equipmentthrough the use of ordinary field labor and supervisory personnel.

It is a further object of this invention to provide a device asaforesaid which operates as long as necessary to isolate a particularsection of tubing but which may be withdrawn without further pluggingeffect on the break or perforation such as would occur in conventionalcementing practice.

The above and other objects will be made clear from the followingdetailed description when taken in connection with the annexed drawings,in which:

FIGURE l is a cross-sectional three-part view in which the three parts(in practice) are in alignment consecutively from left to right of theligure;

FIGURE 2 is a view similar to FIGURE 1, but taken on the line 2 2 ofFIGURE 1;

FIGURE 3 is a view taken on the line 3 3 of URE 2;

FIGURE 4 is a view taken on the line 4 4 of FIG- URE 2;

FIGURE 5 is a section on the line 5 5 of FIGURE 1;

FIGURE 6 is a section on the line 6 6 of FIGURE 5; and

FIGURE 7 is an enlarged detail view of FIGURE 5 in the region of theline 6 6.

Referring now to FIGURE 1, a continuous string of casing is indicated bythe numeral 10, while breaksin the casing at various levels areindicated at 12. Conventionally, such breaks as 12 have been sealed offheretofore by a cementing process in which cement under pressure isdriven from the interior 0f the casing into the breaks 12. The cementingprocess, however, renders the casing below FIG- 3,479,064 Patented Nov.18, 1969 ICC the break irretrievable, and frequently extends well abovethe break, thus rendering even more of the casing irretrievable.

The present invention contemplates means for sealing off considerablelengths of sub-surface casing between predetermined points so that thecasing itself remains retrievable and the instrumentality of thisinvention is equally retrievabe. Such a procedure has the addedadvantage that while it may be desirable at one stage of operation toseal off an intermediate zone which has been broken or perforated, itmay become desirable later to reopen the zone and drain the strataimmediately adjacent the breaks. This, the present invention permitswith ease.

The present invention comprises a pair of concentric pipes, an innerpipe 14 and an outer jacket 16. As shown in FIGURES 2, 3 and 4, eachlength of outer jacket 16 has adjacent each end a plurality of radiallyspaced supporting teeth 18 and has at its upper end a pair of externalrubber sealing cups 20 and a similarly oppositely directed pair 22adjacent its lower end. This arrangement of cups 20 and 22, as shown, isused when the pressure from the strata behind the break or perforationin the casing is greater than that in the well bore. If the break orperforation in the casing is open to strata which is at a lower pressurethan that existing in the Well bore, the cups 20 and 22 would bereversed without other change in the unit. The cups 20 and 22, which areexpendable, are formed of rubber, neoprene or the like with theirinteriors bonded to steel rings. These cups are attached to the jacket16 by welding the aforesaid steel rings to the jacket. The cups shown inthe drawings are the types most commonly used, however, there are othertypes of sealing devices which may be substituted.

The jacket 16 projects well above the rings 20 and well below the rings22. The teeth 18 support, center and guide the interior tube 14, and aresecured thereto to constitute a unit. The upper end of the outer casing16 is grooved to receive an O-ring 28, while the lower portion isgrooved to receive an O-ring 30. Each of the lengths of outer casing 16has between its lowermost ring 22 and its lowermost O-ring 30 a slidablesleeve 32 which is for the purpose of joining one unit with aconsecutive unit, that is, when one casing 16 is aligned with a lowerone, a sliding sleeve 32 can be pressed over the adjacent O-rings 30 and28 of juxtaposed units and thereby effect a fluidtight seal.

The above-described joinder of two or more sections is best shown inFIGURES 5, 6 and 7, where consecutive lengths of the inner tube 14 arejoined by a conventional joint 34 and a tube 32 overlies the O-ring 28of one outer tube 16 and the lower O-ring 30 of the outer casing 16above it. This arrangement provides for considerable flexibility inadjusting relationships of one joint to the next one. It will beunderstood that fluid oil from the bottom of the well rises through theinner pipe 14, while gas from the portion of the well below the last ofthe sealing members rises between the inner tube 14 and the outer casing16 and easily passes between the teeth 18 at each end of a length.

As used in this application, a unit comprises one section of outer shell16, one section of inner tube 14 projecting therethrough, both sectionsbeing secured to the teeth 18 and with the inner tube 14 exceeding inlength the section of outer tube 16. The unit also includes one slidablesleeve 32. As previously noted, a separable joint 34 is made betweenadjacent ends of inner tubes 14 and another separable joint is made bythe sleeve 32 between adjacent ends of outer tubes 16. There is thusdefined an `inner channel or passageway through the inner tube 14 and anouter channel or passageway between the tube 14 and the outer tube 16and the rings 20 and 22 seal off a given portion of well casingcontaining a break or per- 3 foration. The tubes 16 and 14 may becontinued below the lowermost seal ring 22 and may selectively encountereither gas level or oil level below the seal. This automatically selectsthe channel, whether tube 14 -or outer Shell 16, for conveying gas oroil to the surface. Since the seal rings 22 are expendable, there is noproblem in retrieving all of the units and thereafter retrieving thecasing by conventional means.

While certain specific details have been disclosed herein, it is notintended that this invention be limited to the precise detailsdisclosed.

l What is claimed is:

1. A combination sealing and venting unit for oil well use comprising: apair of concentric, imperforate tubes; means between said tubes to holdthem in spaced, coaxial alignment, said means being so formed as toprovide a continuous fluid passageway between the tubes; externalsealing rings secured adjacent to but spaced from each end of the outertube, said unit being adapted to be inserted in an outer casing having abreak or perforation therein whereby said sealing rings engage the innerwall of the casing on both sides of the break or perforations to sealoff the zone having the break or perforation, and the axial bore passagein the inner tube being separated from the uid passageway between thetubes, and an imperforate tubular sleeve means being axially slidable onone end of the outer of said tubes to sealably but detachably join saidunit to the outer tube of a similar unit.

2. A unit as set forth in claim 1, in which said tubular sleeve means ispositioned below the adjacent sealing ring of said outer tube.

3. A unit as set forth in claim 1, in which the length of the inner tubeexceeds that of the outer tube.

4.'A unit as set forth in claim 3, in which the length of the inner tubeexceeds the length of the outer tube at both ends of the outer tube.

5. A unit as set forth in claim 4, in which said tubular sleeve means isbelow the adjacent exterior sealing ring of said outer tube, saidimperforate tubular sleeve means being shorter than either lof saidtubes, and means on each lend of the outer of said pair of concentrictubes for sealingly engaging the walls of the bore of said tubularsleeve means.

References Cited UNITED STATES PATENTS 1,723,682 8/1929 Deming 166-115 X2,569,026 9/1951 Springer 166l46 2,569,437 10/1951 Baker 166-186 X2,722,279 11/1955 Collins 166-147 2,738,012 3/1956 Springer 166-1463,208,539 9/1965 Henderson 175-215 3,361,204 1/1968 Howard et al 166-186X 3,391,743 7/1968 Bateman 166-183 THOMAS F. CALLAGHAN, Primary ExaminerU.S. Cl. X.R.

